For some reason i cant get a dataobject's function canDelete() and canEdit() to work on DataObjectManager. my code works with CTF, but not DOM.

class MyDataObject extends DataObject{
...
     function canDelete(){
		switch($this->Title){
			case 'None':
				return false;
				break;
			default:
				return true;
				break;
		}
		return true;
	}
}

also, with ComplexTableFields, i can call a function through the fieldList in the CTF constructor. I can also get values from relationships through dot notation as well. how can i do this with DOM? here's an example with CTF's:

(in DataObject 'OptionItem')
function weightWithSymbol(){
		return $this->WeightModifier.' lbs';
	}

(in CTF constructor)
$optionSet = new ComplexTableField(
			$this,
			'ProductOptions',
			'OptionItem',
			array(
				'Title' => 'Title',
				'weightWithSymbol' => 'Weight Modifier',
				'PriceModifier' => 'Price Modifier',
				'CodeModifier' => 'Code Modifier',
				'ProductOptionGroup.Title' => 'Option Group'
			),
			'getCMSFields',
			'',
			'ProductOptionGroupID'
		);

thanks,
-Chris